pg.ddx.io pgsql-hackers@postgresql.org mailing list archive help / color / mirror / Atom feed From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: David Rowley <david.rowley@2ndquadrant.com>
Cc: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Cc: Dmitry Dolgov <9erthalion6@gmail.com>
Cc: Jeff Janes <jeff.janes@gmail.com>
Cc: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Cc: Pavel Stehule <pavel.stehule@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: why partition pruning doesn't work?
Date: Wed, 13 Jun 2018 10:39:19 -0400
Message-ID: <28597.1528900759@sss.pgh.pa.us> (raw )
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Robert Haas <robertmhaas@gmail.com> writes:
> Seems reasonable. Really, I think we should look for a way to hang
> onto the relation at the point where it's originally opened and locked
> instead of reopening it here. But that's probably more invasive than
> we can really justify right at the moment, and I think this is a step
> in a good direction.
The existing coding there makes me itch a bit, because there's only a
rather fragile line of reasoning justifying the assumption that there is a
pre-existing lock at all. So I'd be in favor of what you suggest just to
get rid of the "open(NoLock)" hazard. But I agree that it'd be rather
invasive and right now is probably not the time for it.
regards, tom lane
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Cc: tgl@sss.pgh.pa.us, robertmhaas@gmail.com, david.rowley@2ndquadrant.com, Langote_Amit_f8@lab.ntt.co.jp, 9erthalion6@gmail.com, jeff.janes@gmail.com, ashutosh.bapat@enterprisedb.com, pavel.stehule@gmail.com, pgsql-hackers@lists.postgresql.org
Subject: Re: why partition pruning doesn't work?
In-Reply-To: <28597.1528900759@sss.pgh.pa.us>
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